1,721,074 research outputs found
Molecular insights into nanoplastics-peptides binding and their interactions with the lipid membrane
Full text linkMicro- and nanoplastics have become a significant concern, due to their ubiquitous presence in the environment. These particles can be internalized by the human body through ingestion, inhalation, or dermal contact, and then they can interact with environmental or biological molecules, such as proteins, resulting in the formation of the protein corona. However, information on the role of protein corona in the human body is still missing. Coarsegrain models of the nanoplastics and pentapeptides were created and simulated at the microscale to study the role of protein corona. Additionally, a lipid bilayer coarse-grain model was reproduced to investigate the behavior of the coronated nanoplastics in proximity of a lipid bilayer. Hydrophobic and aromatic amino acids have a high tendency to create stable bonds with all nanoplastics. Moreover, polystyrene and polypropylene establish bonds with polar and charged amino acids. When the coronated nanoplastics are close to a lipid bilayer, different behaviors can be observed. Polyethylene creates a single polymeric chain, while polypropylene tends to break down into its single chains. Polystyrene can both separate into its individual chains and remain aggregated. The protein corona plays an important role when interacting with the nanoplastics and the lipid membrane. More studies are needed to validate the results and to enhance the complexity of the systems
Thermostable engineered enzyme
No full textThe invention relates to an engineered PETase enzyme comprises an amino acid sequence having at least 70% or 80%, 90%, 95%, 99% or 100% sequence identity to SEQ ID NO.1. Preferably, the PETase enzyme comprises SEQ ID NO.1 with at least four mutations. The invention also refers to a composition and to a method for decomposing plastics
Modeling and measuring visco-elastic properties: From collagen molecules to collagen fibrils
No full textCollagen is the main structural protein in vertebrate biology, determining the mechanical behavior of
connective tissues such as tendon, bone and skin. Although extensive efforts in the study of the origin of
collagen exceptional mechanical properties, a deep knowledge of the relationship between molecular
structure and mechanical properties remains elusive, hindered by the complex hierarchical structure of
collagen-based tissues. Understanding the viscoelastic behavior of collagenous tissues requires knowledge
of the properties at each structural level. Whole tissues have been studied extensively, but less is
known about the mechanical behavior at the submicron, fibrillar and molecular level. Hence, we
investigate the viscoelastic properties at the molecular level by using an atomistic modeling approach,
performing in silico creep tests of a collagen-like peptide. The results are compared with creep and
relaxation tests at the level of isolated collagen fibrils performed previously using a micro-electromechanical
systems platform. Individual collagen molecules present a non-linear viscoelastic behavior,
with a Young's modulus increasing from 6 to 16 GPa (for strains up to 20%), a viscosity of 3.8470.38 Pa s,
and a relaxation time in the range of 0.24–0.64 ns. At the fibrils level, stress–strain–time data indicate
that isolated fibrils exhibit viscoelastic behavior that could be fitted using the Maxwell–Weichert model.
The fibrils showed an elastic modulus of 123746 MPa. The time-dependent behavior was well fit using
the two-time-constant Maxwell–Weichert model with a fast time response of 772 s and a slow time
response of 10275 s
REACHING THE NORMAL DIFFUSION REGIME WITH AN ATOMIC INFORMED COARSE GRAIN MODEL: DIFFUSION OF BENZENE WITHIN PVA MATRIX
No full textHow to predict diffusion of medium-sized molecules in polymer matrices. From atomistic to coarse grain simulations
No full textDeformation rate controls elasticity and unfolding pathway of single tropocollagen molecules.
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